Threat to the US Counterterrorism Mission in Iraq
In the wake of the airstrike at Baghdad airport on January 3 that killed Qassim Soleimani, commander of the Quds Force, and Abu Mahdi al-Muhandis, deputy commander of the Popular Mobilization forces, there is renewed political support in Iraq for the expulsion of US troops from the country. While this has long been a goal of Iran and its proxies in Iraq to force US troops out, the strike on Soleimani has been a rallying cry particularly among Iraq’s Shia politicians and their supporters. This surge in support for this goal has happened because the agreement between Iraq and the US allows US forces to be stationed in the country to carry out strikes against ISIS and provide training for Iraqi security forces, not to strike Iranian commanders and proxy forces as the strike against Soleimani did. Iraqis see this strike as a violation of their sovereignty and an increased risk of Iraq becoming a battleground in rising tensions between Iran and the US, an outcome many Iraqis believe could be avoided if US troops were no longer stationed in the country. 
The expulsion of US forces in Iraq would be a significant loss in the ongoing effort to defeat ISIS. While ISIS lost the last of its territorial holdings in March of 2019, the group continues to wage a guerilla war in the remote regions of northern Iraq and rebuild its infrastructure. The Department of Defense report for the third quarter of 2019 stated that ISIS carried out 154 primarily small scale attacks and that their rebuilding efforts in Iraq have not been significantly degraded.  Given this clear indication of the continued strength of ISIS to carry out attacks and reconstitute its strength, the removal of US airpower and logistical support for Iraqi security forces from the fight against ISIS would only further strengthen the group and give them further freedom of movement to rebuild. This would also not be the first time removing US support from Iraq had a negative impact on a counterterrorism mission, as the removal of US support after the US withdrawal in 2011 allowed the predecessor organization of ISIS, al-Qaeda in Iraq, to regain its strength and achieve the military success it gained in 2013 and 2014. While it is unlikely that ISIS would be able to completely reconquer its former territory, a US withdrawal will accelerate the regrowth of ISIS networks in Iraq.
It is important to consider the context of the US-led coalition’s presence in Iraq. US troops were invited into the country in June of 2014 after ISIS invaded Iraq and conquered Mosul. In the aftermath of this setback, the US formed a coalition in September of 2014 of 24 nations who committed to providing Iraq military support in the fight against ISIS.  Since then, US troops stationed in Iraq have remained in the low thousands and largely remain in the country in a training capacity and air-support role. US airpower, in particular, was vital in supporting Iraqi forces in their fight against ISIS, and was an important factor in enabling the Iraqi army to push back ISIS forces and retake Mosul in the fall of 2017.
Several political measures have been taken by the opponents to the US presence in Iraq. Just two days after the strike, the Shia aligned political parties in the Iraqi parliament, many of which have strong ties to Iran, pushed through a non-binding resolution to call upon the government to end the authorization for US troops to remain stationed in the country. The government is unlikely to act upon this measure until a new prime minister is named to replace Abdul Mahdi, who remains in a caretaker role since his resignation on November 29. Whether or not his successor chooses to act on the resolution will determine the likelihood of the Iraqi government works towards expelling US troops. In addition, it is important to note the support for this measure by Muqtada al-Sadr, the popular Shia cleric who leads the largest political bloc in parliament, Sairoon. Sadr sees himself as an Iraqi nationalist who in recent years has been at odds with Iran, though he has always been opposed to any foreign influence in the country. Sadr has called upon Shia Popular Mobilization Forces to coordinate their efforts to oppose US forces in the region and has called for peaceful demonstrations against the US presence in Iraq. The first of these demonstrations took place on January 24, and Sadr was able to rally an estimated 200,000 demonstrators for this protest in Baghdad. 
It is important to note that not all of Iraq’s political establishment opposes the US presence in Iraq. The January 5 vote on the resolution to remove authorization for the US troop presence was largely boycotted by the Sunni and Kurdish members of parliament.  The leaders of the Kurdistan Region have also voiced strong support for the continued US role in Iraq, as president Nechirvan Barzani has said in his recent statements that US troops should remain until the threat from ISIS is completely eliminated.  This raises the possibility that if US troops were expelled from Iraq, they may be able to remain at bases in the Kurdistan region. Iraq’s President Barham Salih also voiced his support for continued US troop presence in a recent meeting with President Trump.  Salih is the former prime minister of the Kurdistan region so his support also indicates the strong support among Kurdish politicians for the US role in Iraq.
There is a danger to US troops if they remain stationed in Iraq. While sporadic rocket attacks were carried out against US bases throughout 2019, the frequency of these attacks has increased since the Soleimani strike. Since then, there have been four strikes targeting locations housing US personnel, the latest being on January 20.  While no group has claimed responsibility for these attacks, they were likely carried out by Kataib Hezbollah (KH) or Asib Ahl al-Haq (AAH), two of the strongest Iranian backed proxies. KH, in particular, has warned Iraqi forces to stay away from US bases, an indication that the group continues to target US installations.  KH has also called for volunteers for suicide bombings, though whether they have acted on this statement remains unclear.  These attacks by Iranian proxies are in addition to the Iranian missile attack on January 8, and if tensions between Iran and the US rise again, US bases in Iraq may be targeted again.
Ultimately the resolution of the ongoing political chaos in Iraq will have an impact on how difficult it is for the US to keep its troops in Iraq. The protest movement against the Iraqi government and the Iranian influence in the country which has been ongoing since October has regained its intensity after a brief lull around the Soleimani strike. If public sentiment in the country shifts back to calling for the reform of the Iraqi political system and an end to Iranian influence in the country, the US will have a stronger position to negotiate with a new government on keeping US forces in Iraq. It will also be important for the US mission in Iraq who is chosen as Iraq’s new prime minister, as a pro-Iranian candidate would most likely attempt to follow through with the resolution passed by the parliament. Public support for expelling US troops should also not be underestimated, as the number of demonstrators Sadr was able to gather for his rally shows Iraqis oppose unilateral US strikes in the country.
The United States should prioritize supporting Iraqi politicians who voice clear support for US support. While many of the Iranian aligned politicians opposing US interests in the country are in a strong position in parliament, the boycott of the vote to expel US troops mainly by Kurdish and Sunni politicians shows there are Iraqis who realize the importance of US support in the fight against ISIS. In addition, it is important that the US exercise restraint in striking Iranian backed proxies in Iraq. While organizations like Kataib Hezbollah have clearly been targeting US bases, even before the Soleimani strike the mass protests outside the US embassy in response to US airstrikes against KH are a clear indication of the popular support groups like KH have in Iraq. Public sentiment is shifting against Iranian backed groups due to their role in suppressing the protest movement, and a second strike on these groups would only reverse this trend and further strengthen support for expelling US troops from the country. The US should remain focused on its mission in supporting the fight against ISIS and support the rights of Iraqi protesters who have often been cracked down on by Iraqi authorities.
CTG CENTCOM will continue to closely monitor the political situation in Iraq and watch for any developments that could impact the presence of US troops in the country. In addition, CTG will continue to closely monitor the activities of Iranian backed proxies in Iraq who may increase their attacks on US bases.
The Counterterrorism Group (CTG)
Image Source: ”Combat Training to Combat Troops”, U.S. Marine Corps photo by Cpl. Shellie Hall
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